title: Azithromycin and survival in Streptococcus pneumoniae pneumonia: a retrospective study.
abstract: OBJECTIVE
  Streptococcus pneumoniae (SP) represents a major pathogen in pneumonia. The impact of azithromycin on mortality in SP pneumonia remains unclear. Recent safety concerns regarding azithromycin have raised alarm about this agent's role with pneumonia. We sought to clarify the relationship between survival and azithromycin use in SP pneumonia.
  
  
  METHODS
  Retrospective cohort.
  
  
  METHODS
  Urban academic hospital.
  
  
  METHODS
  Adults with a diagnosis of SP pneumonia (January-December 2010). The diagnosis of pneumonia required a compatible clinical syndrome and radiographic evidence of an infiltrate.
  
  
  METHODS
  None.
  
  
  METHODS
  Hospital mortality served as the primary endpoint, and we compared patients given azithromycin with those not treated with this. Covariates of interest included demographics, severity of illness, comorbidities and infection-related characteristics (eg, appropriateness of initial treatment, bacteraemia). We employed logistic regression to assess the independent impact of azithromycin on hospital mortality.
  
  
  RESULTS
  The cohort included 187 patients (mean age: 67.0±8.2 years, 50.3% men, 5.9% admitted to the intensive care unit). The most frequently utilised non-macrolide antibiotics included: ceftriaxone (n=111), cefepime (n=31) and moxifloxacin (n=22). Approximately two-thirds of the cohort received azithromycin. Crude mortality was lower in persons given azithromycin (5.6% vs 23.6%, p<0.01). The final survival model included four variables: age, need for mechanical ventilation, initial appropriate therapy and azithromycin use. The adjusted OR for mortality associated with azithromycin equalled 0.26 (95% CI 0.08 to 0.80, p=0.018).
  
  
  CONCLUSIONS
  SP pneumonia generally remains associated with substantial mortality while azithromycin treatment is associated with significantly higher survival rates. The impact of azithromycin is independent of multiple potential confounders.
authors.affiliation: Pulmonary and Critical Care Medicine Division, Washington Hospital Center, Washington, District of Columbia, USA.
authors.forename: Andrew F
authors.initials: AF
authors.lastname: Shorr
authors.forename: Marya D
authors.initials: MD
authors.lastname: Zilberberg
authors.forename: Jason
authors.initials: J
authors.lastname: Kan
authors.forename: Justin
authors.initials: J
authors.lastname: Hoffman
authors.forename: Scott T
authors.initials: ST
authors.lastname: Micek
authors.forename: Marin H
authors.initials: MH
authors.lastname: Kollef